In fabric sun-protection performance control, establishing a clear and executable internal UPF (Ultraviolet Protection Factor) quality control standard is key to ensuring product consistency and avoiding market risks. This standard should cover the full process from sample management to result determination, and professional testing equipment is the core support for standard implementation. The CHNSpec UPF-600 Fabric Ultraviolet Protection Factor Analyzer, with stable performance and adaptability, can be seamlessly integrated into an enterprise quality control system. The following is an SOP (Standard Operating Procedure) template for UPF quality control formulated in combination with the device characteristics, provided for enterprises as a reference for execution.
I. Core framework of the SOP: clarify quality control objectives and scope
1. Control objectives
Through standardized testing procedures, ensure that the fabric products produced/purchased by the enterprise have key indicators such as UPF value and UVA transmittance that meet preset quality requirements (for example, meeting the basic requirements for sun-protective products in GB/T18830:2009 where “UPF > 40 and UVA transmittance < 5%”, or the enterprise’s own more stringent standards), and prevent nonconforming products from entering the market.
2. Scope of application
This SOP applies to all fabric samples within the enterprise that require UPF performance testing, including raw fabric materials, semi-finished products, finished products, etc. The testing device is limited to the CHNSpec UPF-600 Fabric Ultraviolet Protection Factor Analyzer.
II. Personnel and equipment management: laying the foundation for standard execution
1. Personnel requirements
- Testing personnel must undergo specialized training, be familiar with the CHNSpec UPF-600 operation procedures (such as sample placement, parameter settings, report export), instrument calibration methods, and safety precautions, and may operate independently only after passing assessment.
- Clarify personnel responsibilities: testers are responsible for sample testing and data recording; quality specialists are responsible for result review and abnormality handling; equipment administrators are responsible for daily maintenance of the instrument and execution of the calibration schedule.
2. Equipment management (taking CHNSpec UPF-600 as an example)
- Daily maintenance: before each day’s testing, inspect whether the instrument appearance is intact, whether the touchscreen is responsive, and whether the sample stage is clean; after testing, turn off the light source and clean residual fibers from the sample stage; weekly, wipe optical components with a dedicated cleaning cloth to avoid dust affecting testing accuracy.
- Regular calibration: perform instrument calibration monthly according to the CHNSpec UPF-600 calibration procedure, using standard calibration samples; record the calibration date, calibration results and operator, to ensure the instrument’s measurement baseline is stable (the instrument supports directly invoking the calibration program via the touchscreen, simplifying the operation steps).
III. Full-process testing specifications: standardized operations from sample to result
1. Sample receipt and pretreatment
- Upon sample receipt, record sample name, batch, quantity, source (e.g., production workshop / supplier) and testing requirements; verify sample condition (no damage, no contamination); samples not meeting requirements should be returned with reasons noted.
- Pretreatment: according to the product’s actual usage scenario, perform corresponding pretreatment per enterprise standards (e.g., simulate 3/5 cycles of routine washing); after pretreatment, place samples in an environment of 23±2°C and relative humidity 50±5% to equilibrate for at least 4 hours before subsequent testing.
2. Sample testing (adapted to CHNSpec UPF-600 operation)
- Sampling: from equilibrated samples, avoid fabric edges and defects, and cut 3 specimens of 100mm × 100mm per standard (ensure specimens are representative).
- Instrument operation:
(1) Turn on the CHNSpec UPF-600 power and wait for instrument self-check to complete (screen displays “Ready”); on the touchscreen select “Enterprise QC Testing” mode (enterprise custom testing parameters can be preset so no need to reset each time).
(2) Smoothly fix the specimen on the instrument sample stage, close the inspection chamber door, and click “Start Test”; the instrument will automatically complete a 280–400nm full-band scan and generate spectral data within 1 second.
(3) The three specimens from the same sample must be tested separately; the instrument will automatically compute the average to avoid single-test errors.
3. Data recording and result determination
- After testing, view and export the test report on the instrument touchscreen; the report must include sample information, test date, instrument number, UPF value, UVA transmittance, UVB transmittance and other key data; hard-copy reports require signatures from the tester and reviewer.
- Result determination: if test data meets enterprise preset quality standards (e.g., UPF ≥ 40, UVA transmittance ≤ 5%), determine “Pass” and allow the product to proceed to the next stage; if not meeting standards, mark as “Fail” and the quality specialist organizes a retest (the retest process follows the initial test); if still failing, initiate the abnormal handling process (e.g., trace raw materials, adjust production process).
IV. Abnormal handling and document management: ensuring closed-loop standard governance
1. Abnormal handling
- If the instrument reports errors during testing (e.g., “sample not positioned”, “calibration failed”), first troubleshoot according to the CHNSpec UPF-600 operation manual (e.g., re-place the sample, re-calibrate); if the issue cannot be resolved, contact the equipment supplier’s technical support and suspend testing to avoid generating invalid data.
- If a high failure rate is detected within the same batch of samples, trace the sample source, analyze whether there are raw material batch issues or pretreatment operation deviations, produce an abnormal analysis report, and use it as the basis for optimizing quality control standards.
2. Document management
- All test reports, calibration records, and abnormal analysis reports must be categorized and archived, with a retention period not less than the product shelf life; electronic files must be backed up to facilitate subsequent traceability and quality audits.
- Periodically (e.g., quarterly) review SOP execution; in conjunction with updates to market standards (e.g., industry standard revisions) and instrument usage feedback, optimize and adjust SOP content to ensure the timeliness and applicability of the quality control standard.
Establishing an internal UPF quality control standard in an enterprise centers on being “executable, traceable, and improvable”, and the CHNSpec UPF-600 Fabric Ultraviolet Protection Factor Analyzer’s standardized operation design (such as preset test modes, automatic data calculation, and convenient report export) can greatly reduce SOP execution difficulty and help enterprises efficiently implement quality control. Through this SOP template, enterprises can quickly build a UPF quality control system, ensure the stability of product sun-protection performance from the source, and enhance market competitiveness.
